Navigated abdominal T1-W MRI permits free-breathing image acquisition with less motion artifact

Abstract
T1-W imaging of the pediatric abdomen is often limited by respiratory motion artifacts. Although navigation has been commonly employed for coronary MRA and T2-W imaging, navigation for T1-W imaging is less developed. Thus, we incorporated a navigator pulse into a fat-suppressed T1-W SPGR sequence such that steady-state contrast was not disrupted. Ten children were scanned after gadolinium administration three times in immediate succession: breath-hold with no navigation, free-breathing with navigation, and free-breathing without navigation. Motion artifacts were scored for each sequence by two radiologists, showing fewer motion artifacts with navigation compared to free-breathing and greater motion artifacts than with breath-holding. This work demonstrates the feasibility and potential utility of navigation for pediatric abdominal T1-W imaging.